JP3219186U - Solar air power generation equipment - Google Patents

Abstract

A solar air power generation facility capable of collecting solar thermal energy to heat air without burning fossil fuel and generating electric power by effectively driving an air turbine, an air compressor and a generator with the heated air. I will provide a. SOLUTION: A solar air power generation facility in which high-temperature air generated by collecting solar heat energy with a starting motor 14 is introduced into an air turbine 6 and the number of revolutions of a generator 13 is increased so that the generator is synchronously inserted into the system. is there. The air condition of the air turbine, which makes the power generation facility economical, is about 0.5 MPa / 600 ° C. [Selection] Figure 1

Description

  The present invention relates to a solar air power generation facility that converts solar thermal energy into electric energy without using fossil fuels.

  Regarding a device for converting solar thermal energy into electrical energy, in Patent Document 1 and Japanese Patent Application Laid-Open No. 2014-1641, carbon dioxide gas is heated by solar thermal energy collected by one tower of solar heat collecting tower, and the carbon dioxide A solar gas turbine power generation system is disclosed in which a carbon dioxide gas turbine is driven with gas to generate both coaxial compressor power and generator power. Further, FIG. 14 of the preceding example discloses an open cycle gas turbine system that generates power by driving an air turbine under conditions of air temperature / pressure: 650 ° C./1.0 MPa.

JP, 2014-1641, A

  In the preceding example, FIG. 9 of Japanese Patent Application Laid-Open No. 2014-1641, in one solar heat collector tower, carbon dioxide gas is heated to drive one carbon dioxide gas turbine, and three compressors directly connected coaxially and 1 A solar power generation device that drives a generator is proposed. The temperature / pressure of carbon dioxide gas produced by the solar heat collector is 650 ° C./20 MPa, which is a high temperature / high pressure. There is a problem that the cost of power generation equipment increases because it is necessary for a wide range of power generation devices. Furthermore, in the configuration of FIG. 9 of the preceding example, the shaft configuration becomes long, and the total weight of the three compressors, the generator, and the turbine increases, so that there is a problem that the start / stop device of this device becomes larger and complicated. .

  Further, in FIG. 14 of the preceding example, it is proposed that an air turbine coaxial with the compressor and the generator is driven by air heated by solar heat to obtain a generator output of 5.8 MWe. There is no explanation about the stop device and the control device. In other words, there is no description of the air turbine power generation device and the control device for starting the compressor that pressurizes the compressor at the inlet and the atmospheric pressure of about 0.1 MPa to about 1.0 MPa. Further, there is no description of the source of the power source that synchronously parallels the generator to the power system and raises the generator speed to the no-load rated speed.

  Further, in FIG. 9 of the preceding example, in order to prevent the high-pressure and high-temperature carbon dioxide gas from the turbine shaft seal portion from leaking outside, the structure of the bearing seal portion is complicated and a large-scale bearing seal device is required. There is also.

Means to solve the problem

  A general air pressure of about 0.1 MPa, an air compressor that compresses the air to about five times the pressure of about 0.5 MPa, a generator that is synchronously parallel to the power system, and a high temperature that is sent from a solar air heater A solar thermal air power generation facility having a start / stop control device and a load operation control device capable of start / stop operation and power generation operation with a coaxial air turbine driven by air has been devised.

  Start up by operating the load so that the power generation load of the solar air power generation device consisting of an air turbine that drives the generator and air compressor and a solar heating device that concentrates sunlight and heats the compressed air can be obtained to the maximum A start / stop control device and a load operation control device were devised.

  In the present invention, when a load interruption of the generator occurs, a shut-off device that shuts off the inflow of air into the air turbine, a device that releases high-temperature and high-pressure air remaining in the air heater device to the atmosphere, and emergency stop control of solar thermal air power generation Have the device.

Effect of device

  The load operation control device according to this study controls the air condition (= planned temperature at the inlet of the air turbine / planned pressure condition) to a constant level, stabilizing the generator output, and obtaining cheap and clean power continuously over a long period of time. The effect is born.

  Furthermore, the start / stop control device and the emergency stop control device can perform an operation for starting and stopping the solar thermal air power generation device and an operation for safely and urgently stopping the solar thermal air power generation device.

  Furthermore, since the present invention is an air turbine power generation system rather than a steam turbine power generation system, a large amount of cooling water for cooling the steam turbine condenser is not required.

The whole basic structure of the control apparatus of the left-side apparatus same as the solar thermal power generation apparatus of embodiment of this invention is shown. Changes in direct solar radiation intensity, generator rotational speed, and power generation load when starting this device are shown. Changes in direct solar radiation intensity, generator speed, and power generation load when this equipment is stopped are shown. The power generation cycle according to the present invention is shown on an air temperature-entropy diagram (Ts diagram). The change in power that can be generated when the turbine inlet temperature is kept constant is shown. The change in power that can be generated when the turbine inlet pressure is constant is shown.

  Forms between each device that collects solar heat and heats the air to drive the air turbine to rotate the generator to generate electricity, and between each control device when the device is in start / stop operation, steady load operation or emergency stop operation Will be described in accordance with the following examples.

  Embodiments will be described below with reference to the accompanying drawings. In FIG. 1, the sunlight from the sun 1 is collected by the solar heat collector 2 and concentrated on the solar heat heater 4 installed at the top of the heat collection tower 3, and then passes from the air compressor 5 through the solar heat collector inlet pipe 24. The compressed air sent is heated. Thereafter, the heated compressed air flows to the air turbine 6 through the solar heat collector outlet pipe 25, drives the air compressor 5 and the generator 13, and generates power for compressing air and power for driving the generator. . The air that has driven the air turbine 6 passes through the air turbine outlet duct 27 and is discharged out of the system.

  A power generation command planned to come from an external system to the power generation apparatus is shown as a system load command 90 in FIG. Further, the planned generator rotational speed is indicated by a generator rotational speed 91 in FIG. The planned generator output is shown in the planned generator output 92. The deviation between the current generator speed and output and the system load command 90 is shown as deviation 93 in FIG. Based on this deviation value, the power generator is controlled in such a direction that the deviation disappears.

  FIG. 2 shows a state in which the solar hot-air power generation facility reaches a rated load 100% load operation around 11:00 in the morning when the sun starts to rise in a certain sunny day. In the time zone A of FIG. 2, rotation of the common shaft 17 of the air compressor 5, the air turbine 6, and the generator 13 is performed by introducing external power to the starting motor 14 shown in FIG. 1 and driving the starting motor 14. Increase the number to about 30%. The number of revolutions of the starting motor is detected by the starting motor speed meter 50, and the signal is transmitted to the turbine speed / load control device 94 to adjust the opening of the adjusting valve 7 to adjust the flow rate at the outlet of the compressor 5, that is, the air. The turbine 6 inlet air flow rate is controlled.

  Next, the direct solar radiation intensity meter 55 detects a state in which the intensity of the direct solar radiation coming from the sun gradually increases with time, and sends it to the solar heat collecting amount control device 95. This control signal is sent to the solar heat collecting device 2 to collect solar heat energy to generate high-temperature air and drive the turbine 6 to increase the rotational speed of the turbine to about 95%. In this process, the clutch 30 is disconnected and the starting motor 14 is stopped. Next, the heated air sent from the solar heating device 4 is sent to the air turbine 6 to increase the number of revolutions of the generator 13 to 100% and synchronously parallel to the system, and at the same time generate about 10% of the parallel load. Power transmission. This is shown in time zone B of FIG.

Next, as the direct solar radiation intensity rises, a signal from the direct solar radiation intensity meter 55 is sent to the solar heat collection amount control device 95 as shown in time zone C, the solar heat collection device 2 is moved, and the load on the generator 13 is reduced. Increase from 10% parallel load to rated 100% load. The power generation output of the power generator 13 is detected by a power generator output meter 52, and the power generation amount is always transmitted to the turbine speed / load control device 94. Hereinafter, after the direct solar radiation intensity reaches about 900 W / m ² , the rated 100% load power generation operation can be continued for several hours as shown in the time zone D as long as the direct solar radiation intensity does not rapidly decrease.

  FIG. 3 shows a state in which the solar altitude begins to fall on a fine sunny afternoon after the continuous load operation is continued for several hours, and the solar hot air power generation facility stops generating power at around 17:00. Following time zone D indicating 100% load, in time zone E of FIG. 3, the generator load is gradually reduced from 100% load to reduce the opening of regulating valve 7 to about 10% disconnection load. Reduce the load to about 10% load. Next, in the time zone F of FIG. 3, the generator 13 is switched from the power transmission generator operation mode to the power receiving motor operation mode. Next, in the time zone G of FIG. 3, the clutch 30 shown in FIG. 1 is connected, and the starter motor 14 is operated by introducing external power to operate the common shaft of the air compressor 5, the air turbine 6, and the generator 13. The rotational speed of 17 is kept at about 30%. Next, a signal for stopping the operation of collecting solar heat is output from the solar heat collecting amount control device 95 to the solar heat collecting device 2, and the temperature of the high-temperature air falls, and the signal of the air turbine inlet thermometer 56 of the air turbine 6 is sent to the turbine. This is transmitted to the rotation speed / load control device 94. Next, a full-close signal is output from the left control device to the regulating valve 7, the clutch 30 shown in FIG. 1 is released, and the rotational speed of the common shaft 17 is detected by the common shaft rotational speed meter 51, and the turbine rotational speed / load control device. 94, the rotational speed of the generator 13 is stopped.

  FIG. 4 is a diagram showing on the air temperature-entropy diagram (Ts diagram) the planned state values of each device when the present device is operated at the rated load. That is, on the air temperature-entropy diagram, the heat cycle (compression: (1) → (2), heating: (2) → when the air turbine inlet pressure is 0.5 MPa and the temperature is 873 K (600 ° C.). (3), expansion: (3) → (4), exhaust: (4) → (1)).

The temperature of the inlet air of the air compressor 5 is about 15 ° C. (= 288 K) at room temperature. The pressure is about 0.1 MPa. This reference point is indicated by point (1) in FIG. The sucked air is compressed by a compressor and the pressure is increased to about 0.5 MPa. This corresponds to point (2) in FIG.

  The compressed air rises to about 280 ° C., but further heats the air with solar heat to raise the air turbine inlet temperature to about 600 ° C. (= 873 ° C.). This point is indicated by point (3) in FIG. The air of (3) is expanded to 0.1 MPa and the air turbine 6 is driven to obtain compression power and power generation power. This point is indicated by point (4) in FIG.

  FIG. 5 shows the results of trial calculation of the change characteristics of the compressor power, turbine power, and power that can be generated when the air turbine inlet temperature is kept constant at 600 ° C. and the air turbine inlet pressure is increased. Compressor power increases as the air turbine inlet pressure increases. However, the increase rate of the obtained turbine power decreases, and when the air turbine inlet pressure is about 1.8 MPa, the compressor power becomes less than the power that can be generated. The power that can be generated is a value obtained by subtracting the power necessary for the compressor from the power generated by the air turbine. When the air turbine inlet pressure decreases, the power that can be generated increases rapidly from around 0.5 MPa, but the specific volume of air also increases. Therefore, the air turbine inlet pressure is reduced to 0. A reasonable pressure is around 5 MPa.

  That is, considering the pressure loss of the related piping, heat exchanger, and regulating valve 7, a reasonable air turbine inlet air pressure is around 0.5 MPa.

  FIG. 6 shows the results of trial calculation of change characteristics of compressor power, turbine power, and power that can be generated when the air turbine inlet pressure is kept constant at 0.5 MPa and the air turbine inlet temperature is increased. Since the air turbine inlet pressure is constant at 0.5 MPa, the compressor power supplied from the air turbine 6 to the air compressor 5 is constant regardless of the air turbine inlet temperature. The power that can be generated is power obtained by subtracting the air compression power of the compressor from the power generated by the air turbine. When the air turbine inlet temperature increases, the power that can be generated increases. However, when the air turbine inlet temperature is about 600 ° C., the rate of increase in power generated by the air turbine 6 decreases, and the rate of increase in power that can be generated also decreases. . Therefore, there is a reasonable air turbine inlet temperature around the air turbine inlet temperature of about 600 ° C.

  In other words, the lower the temperature, the lower the temperature required to use the alloy steel for the pipes and the materials of the respective exchangers, and the usable range of the carbon steel cheaper than the alloy steel is expanded. Reducing the range of use of expensive alloy steel as much as possible enables an economical power generation facility.

  In addition, the selection of air turbine inlet air pressure and temperature affects the power generation power, and at the same time, affects the equipment costs of related piping, heat exchangers, and devices. It is necessary to select the temperature conditions.

  When the power generation is urgently stopped, the regulating valve 7 shown in FIG. 1 is fully closed and the shut-off device 10 is fully closed to interrupt the air flow urgently. At the same time, the atmospheric discharge device 11 is opened to discharge the high-temperature air remaining in the air heating system and reduce the pressure. That is, the high-temperature compressed air remaining in the shut-off device 10, the solar heating device 4, and each pipe is discharged to the atmosphere through the atmospheric discharge device 11 to block the air flowing into the air turbine 6 to prevent acceleration of the generator 13. Take measures.

  When the power generation load is cut off urgently, an emergency stop signal from the turbine speed / load control device 94 is transmitted to the cut-off device 10, and the flow of hot air flowing into the air turbine 6 is cut off. At the same time, an emergency release signal is sent from the turbine speed / load control device 94 to the atmospheric discharge device 11, and the high-temperature air remaining inside the equipment is released to the atmosphere.

  The optimum pressure / temperature trial calculation examples described in FIG. 5 and FIG. 6 are calculated without considering the air throttle loss at the regulating valve 7, the pressure loss of each device, and the heat dissipation loss of each device. Considering the loss, the power generation possible amount is slightly lower than the output described with reference to FIGS. However, these losses are small compared to the power generated by the air turbine 6, and the reasonable temperature / pressure (600 ° C./0.5 MPa) conclusion shown in FIGS. 5 and 6 is not changed.

  This trial calculation is a trial calculation example per 1 kg / s of air. In an actual general gas turbine, the intake air amount varies depending on the output of the gas turbine and the combustion gas temperature, but it is several tens to several hundreds kg / s. Therefore, it is possible to expect a power generation amount of about several thousand kW to several tens of thousands kW per facility in consideration of the size that can be manufactured by this apparatus.

  The breakdown of power generation costs is roughly divided into the total of fuel costs and power generation equipment costs. Solar thermal power generation has the advantage of not requiring fuel costs. Furthermore, it is necessary to reduce the power generation equipment cost in order to reduce the power generation cost. Therefore, when the planned temperature and pressure at the inlet of the air turbine are lowered to reasonable values, an inexpensive electrical output can be obtained and an economical power generation facility can be obtained.

DESCRIPTION OF SYMBOLS 1 Solar 2 Solar heat collecting device 3 Heat collecting tower 4 Solar heating device 5 Air compressor 6 Air turbine 7 Control valve 10 Shut-off device 11 Atmospheric discharge device 13 Generator 14 Starter motor 15 Compressor inlet filter
16 Compressor inlet duct 17 Common shaft 24 Solar heating device inlet tube 25 Solar heating device outlet tube 27 Air turbine outlet duct 30 Clutch 50 Start-up motor speed meter 51 Compressor shaft speed meter 52 Generator output meter 53 Air turbine inlet pressure Total 54 Compressor outlet pressure gauge 55 Direct solar radiation intensity meter 56 Air turbine inlet thermometer 90 System load command 91 Generator rotation speed 92 Planned generator output 93 Deviation 94 Turbine rotation speed / load control device 95 Solar heat collection control device

Claims (3)

  Starter motor, air compressor connected to the motor via a clutch, an air turbine connected coaxially to the air compressor, a generator driven by the air turbine, and solar heat to heat the air A heating device, a first air passage for communicating the air compressor and the solar heating device, a second air passage for communicating the solar heating device and the air turbine, and the air by the motor at start-up. Turbine rotational speed / load control for driving the compressor to a predetermined rotational speed and driving the air turbine and the compressor to a rated rotational speed by the heated air supplied from the solar heating device through the second air flow path. And a solar air power generation facility.   The solar air / air power generation facility according to claim 1, wherein the turbine rotation speed / load control device controls the air pressure at the turbine inlet to approximately 0.5 MPa and the air temperature to approximately 600 ° C during rated operation of the air turbine.   Installed in the second air flow path, stayed in the compressed air system, and an air shut-off device that prevents the generator acceleration accident by shutting off the air flowing into the air turbine when an emergency load shut-off of the generator occurs The solar thermal air power generation facility according to claim 1, further comprising an atmospheric discharge device that immediately releases the high-temperature compressed air to the atmosphere.

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